Clunk when quick shifting?

[BC240]

I just installed an OEM Exedy Clutch on my s14.. Everything feels good, nice pedal feel, no slipping and whatnot.

Only problem is when I shift and accelerate hard I hear a dull CLUNK in my rear end, is this that bushing in my rear end?? when i'm shifting normally I don't hear anything but if I shift fast (or downshift ) and hammer it theres 100% always a CLUNK.

It seems more pronounced with the new clutch.. probably because it grabs faster and tighter.

[DEAN]

I was having the same problem and it WAS the rear end.

[sterlinge]

probly u joints, tranny mount or subframe bushings if you get under your car turn the driveshaft back and forth and see if there is any play in the u joints

[BC240]

Originally Posted by sterlinge

probly u joints, tranny mount or subframe bushings if you get under your car turn the driveshaft back and forth and see if there is any play in the u joints

If i'm in neutral and my car is on the ramp, the U joint (driveshaft/tranny?) should have no play?

[clark]

Originally Posted by BC240

If i'm in neutral and my car is on the ramp, the U joint (driveshaft/tranny?) should have no play?

BC240,
alright I'm going to tell you right now it's probably two things.

1. very common for sub frame bushings to have worn. however, everyone on this forum says that very quickly without asking for your exact symptoms. a lot of things could be causing the clunk.

2. i've personally had a clunk which is my differential. if you have too much backlash, your diff will clunk. meaning there is too much gap between the pinion gear and ring gear.

what you need to do is go under and do some investigation. unbolt your driveshaft from your differential (4 bolts, 14MM). remove the shaft. make sure your e-brake is engaged, and spin the differential flange with your hand. does it clunk when you twist it?? if so, that's most likely the clunk...

if that seems alright, start inspecting your subframe bushings. you need to test with a pry bar or something, get it in there, and start moving htings around with some force. if you have excessive wobble and play, your subrame bushings are gone.

[s13 @ fullboost]

Its most likley your diff based off the fact when you shift smooth everything is good and when down/hard up shifting there is clunking

[BC240]

Originally Posted by clark

BC240,
alright I'm going to tell you right now it's probably two things.

1. very common for sub frame bushings to have worn. however, everyone on this forum says that very quickly without asking for your exact symptoms. a lot of things could be causing the clunk.

2. i've personally had a clunk which is my differential. if you have too much backlash, your diff will clunk. meaning there is too much gap between the pinion gear and ring gear.

what you need to do is go under and do some investigation. unbolt your driveshaft from your differential (4 bolts, 14MM). remove the shaft. make sure your e-brake is engaged, and spin the differential flange with your hand. does it clunk when you twist it?? if so, that's most likely the clunk...

if that seems alright, start inspecting your subframe bushings. you need to test with a pry bar or something, get it in there, and start moving htings around with some force. if you have excessive wobble and play, your subrame bushings are gone.

Thanks for the informative response. I had the driveshaft out when I was replacing my clutch on Saturday, I twisted the it while still in place in order to get to some of the bolts and heard no clunking.. could try again.

I don't quite get how to test the subframe bushing(s)? can you elaborate a little? do I have to jack up my rear end, where do I put the crowbar? sorry for my ignorance i've never had to test or replace such things.

[JDMwannaBE]

i've owned three S14's now and i've had the same problem on all three. everytime it was worn subframe bushings.

[BC240]

Originally Posted by JDMwannaBE

i've owned three S14's now and i've had the same problem on all three. everytime it was worn subframe bushings.

Yeah I don't hear any clunking in the driveshaft while manipulating it manually.. Is there a post on how to check and/or change subframe bushings?

[clark]

just go in there and manhandle the subframe with the crow bar. the subframe bolts to the chassis using 4 studs. you can't miss it. so there are 4 mounting points. shove your crow bar in there and pry around. if things move excessively you've got a problem.


i advise you go back and check again. because you probably didn't notice the problem before since you weren't looking. but if your eally didn't hear clunking in the diff when you turned the flange, then it's highly likelhy that your subframe bushings are the culprit.

start reasearching "subframe collars" and "subframe spacers"

[BC240]

Originally Posted by clark

just go in there and manhandle the subframe with the crow bar. the subframe bolts to the chassis using 4 studs. you can't miss it. so there are 4 mounting points. shove your crow bar in there and pry around. if things move excessively you've got a problem.


i advise you go back and check again. because you probably didn't notice the problem before since you weren't looking. but if your eally didn't hear clunking in the diff when you turned the flange, then it's highly likelhy that your subframe bushings are the culprit.

start reasearching "subframe collars" and "subframe spacers"

Thanks, one more question.. when I'm moving the driveshaft do both my rear wheels need to be off the ground?

[s14canyoncity]

hmmm im getting the same noise, i thought it was just my exhaust shaking and hitting the diff. but this thread got me worried.

mine started when i replaced the RUCA, Toe, Trac arm (SPC). I thought i fucked up and forgot to tighten the bolts. i check all the bolts and fixed the broken hanger on my exhaust. but still getting a clunk noise from the rear when accelerating.

gonna have to check out the following suggestion on this thread.

[JDMwannaBE]

Originally Posted by s14canyoncity

hmmm im getting the same noise, i thought it was just my exhaust shaking and hitting the diff. but this thread got me worried.

mine started when i replaced the RUCA, Toe, Trac arm (SPC). I thought i fucked up and forgot to tighten the bolts. i check all the bolts and fixed the broken hanger on my exhaust. but still getting a clunk noise from the rear when accelerating.

gonna have to check out the following suggestion on this thread.

it's not gonna cause you any huge problems. it's just annoying to hear it all the time. just get back there, and raise the rear up and start flexing the subframe with a bar, and you'll see the slack in the bushings. you can replace them with some better ones or even weld them solid if you'd like that really stiff feeling in the rear.